Polymeric molded sweeping device

ABSTRACT

A sweeping device such as a head for a broom. The device has a first portion (22), including a socket (18) formed as an integral moulding of a relative hard polymeric material. A bristle portion (24) formed from a relatively soft polymeric material is molded to partially envelop the first portion and to engage positively with a groove (32) and undercut (34) formed in the first portion in order to attach the bristle portion to the first portion. The bristle portion is formed with a plurality of integral bristles (20) some of which may have a different cross section from that of the remainder of the bristles.

FIELD OF THE INVENTION

The present invention relates to a sweeping device and in a particularnon-limiting aspect relates to a sweeping device which can be producedby a two stage process of moulding plastics material.

BACKGROUND OF THE INVENTION

There are numerous types of broom head constructions. A typical broomhead construction of the same general nature as that provided byapplicant's invention includes a head portion which may often be formedof wood or similar material having a plurality of holes drilledtherethrough. The holes are used to locate and attach a number ofbristles which protrude below the broom head. In addition, a socket maybe provided as a separate element attached to the head or alternativelyit may simply comprise a hole drilled in the upper part of the head.Whilst such broom head constructions are effective, there is anunacceptably high number of operations involved in the shaping of thehead, the formation of the holes, the cutting of the bristles to size,attachment of socket and broom handle and finally the attachment of thebristles in the plurality of holes.

More recently it has been proposed to produce broom heads by a plasticsmoulding operation. Thus it is possible to mould the broom head, thesocket for a broom stick and the bristles in one operation. However,construction of a broom head in this manner leads to unacceptablecompromises as it is generally necessary to use a relatively softmaterial for the material forming the bristles whereas it is preferredthat the material of the head portion and socket be relatively hard.This is because the head portion and socket must be used to transfer theforce of a broom user to the bristles without the head and socketbending or becoming distorted. Where the broom is made in a singlemoulding operation, because the bristles, head and socket are all madeof the same material, generally speaking, the bristles may be too hardbecause the plastics material has been chosen to provide sufficienthardness for the head and socket, or alternatively the head and socketare too soft because the plastics material has been chosen to providegood bristle properties.

Thus there is a need for an alternative broom construction which can beformed using a plastics moulding operations yet can provide a broom withrelatively soft bristles and a relatively hard head and socket.

DISCLOSURE OF THE INVENTION

In one aspect the invention provides a sweeping device including a headportion having an upper surface and a lower surface, a socket forattaching the sweeping device to a broom stick formed on the uppersurface, and a moulded bristle portion having a plurality of integrallyformed bristles engaged with the head portion, the bristle portion beingformed of a material of lesser hardness than the material forming thehead portion.

The head portion may be moulded. It may be formed of a polymericmaterial. The head portion may have a Shore hardness (as measured in theA scale) in excess of 70.

Suitably the polymeric material includes polypropylene or a copolymer ofpolystyrene and polypropylene. It may include a filler. Preferably thefiller may comprise 10% to 40% by weight of the polymeric material, morepreferably 15% to 25% by weight. Talc is a suitable filler. Thepolymeric material may include a fibrous reinforcement. The fibrousreinforcement may include glass fibre. The fibrous reinforcementsuitably comprises 10% to 20% by weight of the polymeric material.

The bristle portion may be moulded. It may be formed of a bristlecomposition incorporating a polymeric material. The bristle compositionmay include one or more fillers and/or reinforcement materials.Preferably the bristle composition will include a proportion of rubbermaterial. It may also include a proportion of plastics material.

Suitably the socket is formed integrally with the head portion. Thesocket may be located intermediate the ends of an elongate reinforcementmember forming part of the head portion. One or more reinforcing websmay extend between the socket and the elongate reinforcement.

Attachment means may be provided on the head portion to facilitateattachment of the bristle portion thereto. The attachment means mayinclude profile features on the bristle portion. Preferably the profilefeatures include one or more grooves, recesses or raised portions. Mostpreferably, the profile features include a groove. The groove may beprovided on the upper surface of the reinforcement member. Suitably thegroove extends substantially around the reinforcement member near theperimeter thereof. The groove may be undercut.

Preferably the upper surface of the head portion is stepped. The grooveis most suitably formed in a stepped portion of the reinforcementmember.

Raised portions may suitably be provided on the lower surface of thereinforcement member. The raised portions may be in the form ofprojections, lugs or stippling.

The bristle portion may overlie and/or envelop part of the attachmentmeans. It may be provided with a plurality of integral bristles whichextend beneath the lower surface of the head portion.

A proportion of the bristles may have a greater cross-sectional areathan the remainder of the bristles.

A proportion of the bristles may have a D shaped rectangular or squarecross section.

Preferably the bristle portion is formed with a squeegee blade.

In accordance with another aspect of the present invention there isprovided a method of manufacturing a sweeping device, including thesteps of moulding a head portion with a socket extending therefrom andmoulding a bristle portion of softer material than the material formingthe head portion to overlie and partially envelop the first portion toattach the bristle portion to the head portion.

Preferably the material of the bristle portion is moulded to overlie andengage one or more recessed and/or projecting proportions formed in thehead portion.

Suitably the bristle proportion is moulded onto the head portion in sucha manner as to leave the socket and central portion of the head portionfree of overlap with the bristle portion.

The present invention will now be described by way of example withreference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front elevation of a sweeping device in accordance with thepresent invention;

FIG. 2 is a plan view of the sweeping device of FIG. 1;

FIG. 3 is a rear view of the sweeping device of FIG. 1;

FIG. 4 is an underneath view of the sweeping device of FIG. 1;

FIG. 5 is a side elevation of the sweeping device of FIG. 1;

FIG. 6 is an upper perspective view of the sweeping device of FIG. 1;

FIG. 7 is a cross section 7/7 on FIG. 2;

FIG. 8 is a plan view of a moulding component forming part of thesweeping device shown in FIG. 1;

FIG. 9 is an underneath view of the component shown in FIG. 8; and

FIG. 10 is a cross-section 10/10 on FIG. 8.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

In the drawings there is shown a sweeping device 10 comprising a head 12having an upper surface 14 and lower surface 16. A socket 18 is locatedon the upper surface for attachment of a broom stick (not shown) to thehead 12.

Further, a plurality of bristles 20 extend from the lower surface 16.

The head 12 comprises a first portion 22 which is in the form of a firstintegral moulding of a relatively hard polymeric material. The firstportion 22 includes an upper surface 30 which is stepped. A groove 32 isprovided in the lower step and is formed by the under cut 34 extendingaround the first portion 22. The socket 18 is located intermediate theends of the first portion. It forms an integral part of the firstportion and is reinforced by two transverse webs extending to therelatively flat elongate region of the first portion 22 from either sideof the socket.

The first portion 22 may be formed of a plastics material, such aspolypropylene, which may contain a proportion of talc such as about 20%by weight, for increased hardness. On its lower surface 36 the firstportion 22 preferably has a series of integral projections 38 formedthereon. The head 12 also comprises a second portion 24 which is in theform of a second integral moulding of a relatively soft polymericmaterial. The second portion 24 may be formed of a combination of rubberand plastics material. Further, the second portion preferably has aShore A hardness of 35 to 85, more preferably 50 to 75 and mostpreferably 60 to 70, to give a good sweeping action.

The second portion 24 has projecting from its lower surface the bristles20.

The head 12 is typically manufactured by first moulding the firstportion 22 in a single piece complete with the socket 18 and theperipheral groove 32 and the projections 38 described above. The firstportion 22 is then placed in a further mould and the material of thesecond portion is injection moulded into the second mould. The materialof the second portion 24 enters the peripheral groove 32 and engagestherewith. This engagement is positively reinforced by the undercut inthe groove as the material of the second portion 24 engages with theundercut.

Further, the projections 38 on the underside of the first portion 22engage with the material of the second portion 24 to ensure a positiveengagement between the first and second portions 22 and 24 in thisregion of the sweeping device 10.

It is preferred that the central portion of the upper surface of thefirst portion 22 be free of the material of the second portion 24. Toachieve this, in the second mould, the upper surface of the firstportion is typically pushed hard against the roof of the second mould.This may be achieved by deleting some of the bristles 20 and replacingsome of the second mould with metal rods which push the upper surface ofthe first portion 22 up against the roof of the second mould. In thisway the central portion of the upper surface of the first portion 22 canbe kept substantially free of the material of the second portion.

Furthermore, as can be seen in FIG. 4, at least some of the bristlesdenoted by the reference numeral 28 have a larger cross-section orlonger perimeter than the other bristles. Whilst the bristles 28 areillustrated as having a D shaped cross section, it is to be understoodthat other cross-sections such as square, rectangular, hexagonal, etcmay be employed as well. The D shaped or other shaped bristles can beanywhere on the sweeping device 10 such as at the back or at the frontor all over the device 10. The D shaped bristles help to pick up finehair or lint. The embodiment shown works better with a pull towardaction as the D bristles are at the rear of the sweeping device 10.

The use of the polymeric material for the second portion including thebristles 20, has the advantage that the polymeric material may becomeelectrostatically charged and may attract dust particles and hairsthereto. Also, as can be seen in FIG. 5, the second portion 24preferably includes a forwardly projecting squeegee blade 26.

The use of a harder material for the first portion makes it easier tocontrol the second portion which includes bristles by way of keeping itin even contact with a surface being swept. If the first portion is toosoft the socket portion forming part of the first portion may bendcausing the broom head to tilt with the result that only one edge of thebristles contacts the surface being swept.

While it has been convenient to describe the invention herein inrelation to particularly preferred embodiments, it is to be appreciatedthat other constructions and arrangements are considered as fallingwithin the scope of the invention. Various modifications, alterations,variations and/or additions to the constructions and arrangementsdescribed herein are also considered as falling within the scope andambit of the present invention.

I claim:
 1. A sweeping device including a moulded head portion having anupper surface and a lower surface, a socket for attaching the sweepingdevice to a broom stick moulded on the upper surface, integral with thehead portion and of the same material as the rest of the head portion,and a moulded bristle portion having a plurality of integrally formedbristles engaged with the head portion, the bristle portion being formedof material of lesser hardness than the material forming the headportion, and the socket being located intermediate the ends of anelongate reinforcement member forming part of the head portion.
 2. Asweeping device according to claim 1 wherein the head portion is mouldedfrom a composition including a substantial proportion of polymericmaterial.
 3. A sweeping device according to claim 2 wherein thepolymeric material is polypropylene or a co-polymer of polypropylene andpolystyrene.
 4. A sweeping device according to claim 2 wherein thematerial of the head portion includes 10% to 45% by weight of talc.
 5. Asweeping device according to claim 4 wherein the material of the headportion includes 15% to 25% by weight of talc.
 6. A sweeping deviceaccording to claim 1 wherein the bristle portion is moulded from acomposition which includes a rubber material.
 7. A sweeping deviceaccording to claim 6 wherein the bristle portion is moulded from acomposition which also includes a proportion of plastic material.
 8. Asweeping device according to claim 1 wherein the socket is reinforced byone or more reinforcing webs extending between the socket and theelongate reinforcement member.
 9. A sweeping device according to claim 1wherein the head portion includes attachment means for facilitatingattachment of the bristle portion thereto.
 10. A sweeping deviceaccording to claim 9 wherein the attachment means include one or moregrooves, recesses, raised portions or projections formed on the headportion.
 11. A sweeping device according to claim 9 wherein the bristleportion partly overlies and/or envelops the attachment means.
 12. Asweeping device according to claim 1 wherein a groove is provided toextend substantially around the elongate reinforcement member near theperimeter thereof.
 13. A sweeping device according to claim 1 whereinthe lower surface of the head portion is provided with raised portionsin the form of projections, lugs or stippling.
 14. A sweeping deviceaccording to claim 1 wherein a proportion of the bristles have a largercross-section than the remainder of the bristles.
 15. A sweeping deviceaccording to claim 14 wherein the bristles of larger cross-section havea D, rectangular or square shaped cross-section.
 16. A sweeping deviceaccording to claim 1 wherein the bristle portion includes a squeegeeblade integrally formed therewith.
 17. A method of manufacturing asweeping device including the steps of moulding a head portion with asocket extending therefrom and thereafter moulding a bristle portion ofsofter material than the material forming the head portion to overlieand partially envelop the first portion to attach the bristle portion tothe head portion said bristle portion being moulded with a plurality ofintegrally formed bristles.
 18. A method according to claim 17 whereinthe material of the bristle portion is moulded to overlie and engage oneor more recessed and/or projecting portions formed in the head portion.19. A method according to claim 18 wherein the bristle portion ismoulded onto the head portion in such a manner as to leave the socketand central portion of the head portion free of overlap with the bristleportion.